61615990 has 32 divisors (see below), whose sum is σ = 120178080. Its totient is φ = 22654464.

The previous prime is 61615987. The next prime is 61615999. The reversal of 61615990 is 9951616.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61615999) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3096 + ... + 11524.

It is an arithmetic number, because the mean of its divisors is an integer number (3755565).

Almost surely, 2^61615990 is an apocalyptic number.

61615990 is a deficient number, since it is larger than the sum of its proper divisors (58562090).

61615990 is a wasteful number, since it uses less digits than its factorization.

61615990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8496.

The product of its (nonzero) digits is 14580, while the sum is 37.

The square root of 61615990 is about 7849.5853393667. The cubic root of 61615990 is about 394.9703337224.

The spelling of 61615990 in words is "sixty-one million, six hundred fifteen thousand, nine hundred ninety".